WO2021059942A1 - Procédé destiné à récupérer du scandium - Google Patents

Procédé destiné à récupérer du scandium Download PDF

Info

Publication number
WO2021059942A1
WO2021059942A1 PCT/JP2020/033775 JP2020033775W WO2021059942A1 WO 2021059942 A1 WO2021059942 A1 WO 2021059942A1 JP 2020033775 W JP2020033775 W JP 2020033775W WO 2021059942 A1 WO2021059942 A1 WO 2021059942A1
Authority
WO
WIPO (PCT)
Prior art keywords
scandium
neutralization
solution
treatment
filtrate
Prior art date
Application number
PCT/JP2020/033775
Other languages
English (en)
Japanese (ja)
Inventor
達也 檜垣
寛人 渡邉
Original Assignee
住友金属鉱山株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2020091441A external-priority patent/JP7327276B2/ja
Application filed by 住友金属鉱山株式会社 filed Critical 住友金属鉱山株式会社
Publication of WO2021059942A1 publication Critical patent/WO2021059942A1/fr

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
    • C22B3/42—Treatment or purification of solutions, e.g. obtained by leaching by ion-exchange extraction
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
    • C22B3/44—Treatment or purification of solutions, e.g. obtained by leaching by chemical processes
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B59/00—Obtaining rare earth metals
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

Definitions

  • the present invention relates to a scandium recovery method, and more particularly to a scandium recovery method for efficiently recovering scandium from a scandium-containing solution obtained from a raw material such as nickel oxide ore.
  • Scandium is extremely useful as an additive for high-strength alloys and as an electrode material for fuel cells, but it has not been widely used due to its low production volume and high cost.
  • Nickel oxide ores such as laterite ore and limonite ore contain a small amount of scandium.
  • nickel oxide ore has a low nickel grade and has not been industrially used as a nickel raw material for a long time. Therefore, the industrial recovery of scandium from nickel oxide ore has also been rarely studied.
  • Patent Document 2 There is also a method of separating scandium using a chelate resin (see Patent Document 2). Specifically, in the method shown in Patent Document 2, first, nickel and scandium are selectively leached into an acidic aqueous solution under a high temperature and high pressure in an oxidizing atmosphere, and then the obtained acidic solution is prepared. After adjusting the pH to the range of 2-4, nickel is selectively precipitated and recovered as a sulfide by using a sulfide agent. Next, scandium is adsorbed by contacting the obtained solution after recovering nickel with a chelate resin, the chelate resin is washed with a dilute acid, and then the washed chelate resin is brought into contact with a strong acid to remove the scandium from the chelate resin. Elute scandium.
  • an aqueous scandium-containing solution containing at least one of iron, aluminum, calcium, yttrium, manganese, chromium, and magnesium is prepared in 2 -Ethylhexyl sulfonic acid-mono-2-ethylhexyl diluted with kerosine is added to the organic solvent, and the scandium component is extracted into the organic solvent. Then, in order to separate ittium, iron, manganese, chromium, magnesium, aluminum, and calcium extracted together with scandium in an organic solvent, they were removed by scrubbing with an aqueous hydrochloric acid solution, and then in the organic solvent.
  • aqueous NaOH solution is added to make scandium remaining in the organic solvent into a slurry containing Sc (OH) 3 , and this is filtered to dissolve Sc (OH) 3 in hydrochloric acid to obtain an aqueous scandium chloride solution.
  • oxalic acid is added to the obtained scandium chloride aqueous solution to form a scandium oxalate precipitate, and the precipitate is filtered to separate iron, manganese, chromium, magnesium, aluminum, and calcium into the filtrate.
  • High-purity scandium oxide is obtained by baking.
  • Patent Document 4 describes a method of selectively separating and recovering scandium from the scandium-containing feed solution by contacting the scandium-containing feed solution with the extractant at a constant ratio by batch processing.
  • the grade of scandium recovered by these methods has a purity of about 95% to 98% in terms of scandium oxide.
  • it is of sufficient quality for applications such as addition to alloys, it has higher purity for applications such as fuel cell electrolytes, for which demand has been increasing in recent years, in order to exhibit good characteristics. For example, a quality of about 99.9% is required.
  • Nickel oxide ore contains various impurity elements such as manganese and magnesium in addition to iron and aluminum, although the type and amount vary depending on the region of production.
  • scandium When scandium is used as an electrolyte for fuel cells, it has an acceptable upper limit depending on the impurity element, and it is necessary to separate and remove each element to the allowable upper limit or less.
  • Patent Document 5 proposes a method for separating scandium and impurity elements by adding a neutralizing agent to an eluent in which scandium is eluted from a chelate resin and controlling the pH in two steps. ..
  • a neutralizing agent to an eluent in which scandium is eluted from a chelate resin and controlling the pH in two steps. ..
  • the aluminum concentration is high, there is a problem that the amount of nickel coprecipitated in the second stage neutralization treatment increases and the nickel grade in scandium oxide increases.
  • Japanese Unexamined Patent Publication No. 3-173725 Japanese Unexamined Patent Publication No. 9-194211 Japanese Unexamined Patent Publication No. 9-291320 International Publication No. 2014/11216 Japanese Unexamined Patent Publication No. 2017-13350
  • the present invention has been proposed in view of such circumstances, and an object of the present invention is to provide a method for recovering scandium capable of efficiently recovering high-purity scandium from a solution containing impurities together with scandium. To do.
  • the present inventors have made extensive studies to solve the above-mentioned problems.
  • the eluate obtained by passing an acidic solution containing scandium through an ion exchange resin was subjected to a neutralization treatment including the addition of a neutralizing agent and dimethylglyoxime, and after neutralization obtained.
  • a neutralization treatment including the addition of a neutralizing agent and dimethylglyoxime, and after neutralization obtained.
  • high-purity scandium can be easily and efficiently recovered from nickel oxide ore by subjecting the eluate to solvent extraction, and have completed the present invention.
  • a solution containing scandium is passed through an ion exchange resin, and a neutralizing agent and dimethyl glyoxime are added to the eluent eluted from the ion exchange resin for neutralization treatment.
  • the second invention of the present invention is a method for recovering scandium, wherein the scandium-containing solution is a solution obtained by leaching a nickel-containing raw material with an acid in the first invention.
  • the dimethylglyoxime in the first or second invention, in the neutralization step, is added in an amount of 3 to 50 equivalents with respect to the amount of nickel contained in the eluent. This is a method for recovering scandium, which is added in proportion.
  • the neutralization step is neutralized by adding a neutralizing agent and dimethylglioxime to the eluent.
  • a method for recovering scandium which comprises a second neutralization step of obtaining a secondary neutralized starch and a secondary neutralized filtrate by liquid separation.
  • a fifth invention of the present invention is a method for recovering scandium, wherein in the first neutralization step, the pH of the eluent is adjusted to the range of 3.8 to 4.5 in the fourth invention. Is.
  • the pH of the primary neutralization filtrate is adjusted to the range of 5.5 to 6.5. This is a method for recovering scandium.
  • an acid is further added to the neutralized starch obtained in the neutralization step to dissolve a hydroxide solvent.
  • This is a method for recovering scandium, which comprises a hydroxide dissolution step of obtaining the above-mentioned product, and in the solvent extraction step, the hydroxide solution is subjected to the solvent extraction treatment as the eluent after neutralization.
  • the eighth invention of the present invention further comprises a recovery step of recovering dimethylglyoxime from the neutralization filtrate obtained in the neutralization step in any one of the first to seventh inventions. It is a collection method of.
  • the neutralization step is performed by adding a neutralizing agent and dimethylglioxime to the eluent to perform a neutralization treatment, and by solid-liquid separation 1
  • the first neutralization step of obtaining the secondary neutralized starch and the primary neutralization filtrate, and the neutralization treatment by further adding a neutralizing agent to the primary neutralization filtrate are performed, and the secondary neutralization is performed by solid-liquid separation.
  • It has a second neutralization step of obtaining a Japanese starch and a secondary neutralization filtrate, and in the recovery step, the secondary neutralization obtained through the second neutralization step in the neutralization step. This is a method for recovering scandium, which recovers dimethylglioxime from the filtrate.
  • the tenth invention of the present invention is a scandium in which the dimethylglyoxime recovered in the recovery step is repeatedly reused in the neutralization treatment in the neutralization step in the eighth or ninth invention. It is a collection method.
  • impurities can be effectively separated from a solution containing impurities together with scandium, and high-purity scandium can be efficiently recovered.
  • the present embodiment a specific embodiment of the present invention (hereinafter, referred to as “the present embodiment”) will be described in detail with reference to the drawings.
  • the present invention is not limited to the following embodiments, and can be carried out with appropriate modifications without changing the gist of the present invention.
  • the notation "X to Y" (X and Y are arbitrary numerical values) means "X or more and Y or less”.
  • FIG. 1 is a process diagram showing an example of a scandium recovery method according to the present embodiment. This scandium recovery method separates scandium and impurities from an acidic solution containing scandium obtained by leaching nickel oxide ore with an acid such as sulfuric acid to easily and efficiently produce high-purity scandium. It is to be collected.
  • the scandium-containing acidic solution which is the target of the scandium recovery method, is not limited to the solution obtained by acid leaching from nickel oxide ore as a raw material.
  • an acidic solution obtained from a raw material containing impurities such as nickel together with scandium can be a suitable target for this recovery method.
  • an eluent obtained by passing an acidic solution containing scandium through an ion exchange resin to adsorb scandium, and then bringing the acid solution into contact with the ion exchange resin (scandium).
  • the eluent is subjected to a neutralization treatment including the addition of dimethylglioxime. This separates impurities and concentrates scandium.
  • the acidic solution in which scandium is concentrated is subjected to solvent extraction using an extractant such as an amine-based extractant to extract impurities contained in the acidic solution into the extractant, and after the extraction, the acidic solution (drawing residue). Separates from scandium that will remain in the liquid).
  • a method of obtaining a hydroxide precipitate by adding an alkali and performing a neutralization treatment, or oxalate formation using oxalic acid for example, a method of obtaining a hydroxide precipitate by adding an alkali and performing a neutralization treatment, or oxalate formation using oxalic acid.
  • a method such as recovery as a precipitate of oxalate by treatment a solid shape suitable for product use is formed, and residual impurities are also separated.
  • scandium is recovered as crystals of high-purity scandium hydroxide or scandium oxalate.
  • the obtained crystals of scandium hydroxide and scandium oxalate are calcined by a known method to obtain the form of scandium oxide.
  • the scandium oxide thus produced can be used as a material for an electrolyte of a fuel cell. Further, it can be used for applications such as obtaining scandium metal by a method such as molten salt electrolysis and then adding it to aluminum to alloy it.
  • the scandium recovery method when the scandium is separated and recovered, dimethylglyoxime is added to the scandium-concentrated solution (eluent) through the ion exchange treatment. It is characterized by performing a neutralization treatment including. As a result, scandium is concentrated, and then a solvent extraction treatment using a solvent extractant is performed. According to such a method, impurities can be separated more effectively, and high-purity scandium can be efficiently produced under stable operation even from a raw material containing many impurities such as nickel oxide ore. Can be recovered.
  • the method for recovering scandium is the wet smelting treatment step S1 of nickel oxide ore to obtain an acidic solution containing scandium by leaching the nickel oxide ore with an acid such as sulfuric acid.
  • a scandium elution step S2 in which impurities are removed from the acidic solution to obtain a scandium eluent in which scandium is concentrated, and a solution containing a high concentration of scandium by neutralizing the scandium eluent (eluent after neutralization).
  • a neutralization step S3 in which the obtained neutralized eluent is subjected to solvent extraction with an amine-based extractant or the like, and a scandium recovery step S5 for recovering scandium from the extraction residue. ..
  • the acidic solution includes a leaching step S11 in which nickel oxide ore is leached with an acid such as sulfuric acid under high temperature and high pressure to obtain a leaching solution, and a neutralized starch containing impurities by adding a neutralizing agent to the leaching solution.
  • Wet smelting treatment of nickel oxide ore having a neutralization step S12 for obtaining a solution after neutralization and a sulfurization step S13 for obtaining a nickel sulfide and a solution after sulfurization by adding a sulfurizing agent to the solution after neutralization.
  • the post-sulfidation solution obtained in step S1 can be used.
  • the flow of the wet smelting treatment step S1 of the nickel oxide ore will be described.
  • Leaching process In the leaching step S11, for example, using a high-temperature pressure vessel (autoclave) or the like, sulfuric acid is added to the slurry of nickel oxide ore and agitated at a temperature of 240 ° C. to 260 ° C., and the leaching solution and the leaching residue are formed. Form an leaching slurry.
  • the treatment in the leaching step S11 may be performed according to a conventionally known HPAL process.
  • Nickel oxide ores mainly include so-called laterite ores such as limonite ore and saprolite ore.
  • the nickel content of the laterite ore is usually 0.8% by weight to 2.5% by weight, and is contained as a hydroxide or a siliceous earth (magnesium silicate) mineral.
  • these nickel oxide ores contain scandium.
  • the leaching solution containing nickel, cobalt, scandium and the like and the leaching residue which is hematite are solid-liquid separated.
  • the solid-liquid separation treatment for example, after mixing the leaching slurry with the cleaning liquid, the solid-liquid separation treatment is performed by a solid-liquid separation equipment such as a thickener using a coagulant supplied from a coagulant supply equipment or the like. Specifically, first, the leaching slurry is diluted with a washing liquid, and then the leaching residue in the slurry is concentrated as a thickener sediment.
  • a solid-liquid separation tank such as a thickener connected in multiple stages and perform solid-liquid separation while washing the leaching slurry in multiple stages.
  • a neutralizing agent is added to the leachate obtained in the leaching step S11 to adjust the pH, and a neutralized starch containing an impurity element and a neutralized liquid are obtained.
  • valuable metals such as nickel, cobalt, and scandium are contained in the liquid after neutralization, and most of the impurities such as iron and aluminum become neutralized starch.
  • neutralizing agent conventionally known ones can be used, and examples thereof include calcium carbonate, slaked lime, sodium hydroxide and the like.
  • the neutralization treatment in the neutralization step S12 it is preferable to adjust the pH to the range of 1 to 4 while suppressing the oxidation of the separated leachate, and it is more preferable to adjust the pH to the range of 1.5 to 2.5. preferable. If the pH is less than 1, neutralization may be insufficient and the neutralized starch and the neutralized liquid may not be separated. On the other hand, when the pH exceeds 4, not only impurities such as aluminum but also valuable metals such as scandium and nickel may be contained in the neutralized starch.
  • a sulfurizing agent such as hydrogen sulfide gas, sodium sulfide, and sodium hydride sulfide is added to the obtained after neutralization liquid, and a sulfide containing nickel with a small amount of impurity components (sulfide).
  • Nickel sulfide) and a post-sulfide liquid containing scandium and the like are produced by stabilizing the nickel concentration at a low level.
  • the nickel sulfide slurry is subjected to a sedimentation separation treatment using a sedimentation separator such as a thickener, and the nickel sulfide is separated and recovered from the bottom of the thickener.
  • a sedimentation separator such as a thickener
  • the post-sulfurization liquid which is an aqueous solution component, is recovered by overflowing.
  • the post-sulfurization solution obtained through each step of the hydrometallurgy step S1 as described above contains scandium and other impurities to be subjected to the scandium recovery treatment. It can be used as an acidic solution.
  • the post-sulfurization solution obtained through each step of the hydrometallurgy step S1 can be applied as an acidic solution which is a target solution for scandium recovery treatment.
  • the acidic solution contains, for example, aluminum, chromium, and various other impurities that remain in the solution without being sulfurized by the sulfurization treatment in the above-mentioned sulfurization step S13. From this, when the obtained acidic solution was subjected to solvent extraction, as the scandium elution step S2, impurities contained in the acidic solution were removed in advance to concentrate scandium (Sc), and a scandium eluent (scandium-containing solution) was used. ) Is preferably generated.
  • impurities such as aluminum contained in the acidic solution can be separated and removed by an ion exchange treatment using a chelate resin to obtain a scandium-containing solution in which scandium is concentrated. ..
  • FIG. 2 is a process diagram showing an example of a scandium recovery method.
  • the process diagram of FIG. 2 shows an example of a method (ion exchange treatment step) performed by an ion exchange reaction using a chelate resin as a method of removing impurities contained in an acidic solution to concentrate and elute scandium. It is a thing.
  • scandium is adsorbed by contacting the post-sulfurized liquid obtained in the sulphurization step S13 in the hydrometallurgical treatment step S1 of nickel oxide ore with a chelate resin to obtain a scandium (Sc) eluate.
  • the ion exchange treatment step as an example of the scandium elution step S2 is referred to as “ion exchange treatment step S2”.
  • the ion exchange treatment step S2 includes an adsorption step S21 in which the post-sulfurized liquid is brought into contact with the chelate resin to adsorb scandium to the chelate resin, and a chelate resin is brought into contact with sulfuric acid of 0.1 N or less to form the chelate resin.
  • An example thereof includes a chromium removing step S24 in which the resin is brought into contact with sulfuric acid of 3N or more to remove the chromium adsorbed on the chelate resin.
  • a chromium removing step S24 in which the resin is brought into contact with sulfuric acid of 3N or more to remove the chromium adsorbed on the chelate resin.
  • each step will be outlined, but the ion exchange processing step S2 is not limited to this.
  • the post-sulfide liquid is brought into contact with the chelate resin, and scandium in the post-sulfurization liquid is adsorbed on the chelate resin.
  • the type of chelate resin is not particularly limited, and for example, a resin having iminodiacetic acid as a functional group can be used.
  • the aluminum removing step S22 sulfuric acid of 0.1 N or less is brought into contact with the chelate resin adsorbed with scandium in the adsorption step S21 to remove the aluminum adsorbed on the chelate resin.
  • the pH of the sulfuric acid solution is preferably maintained in the range of 1 or more and 2.5 or less, and more preferably 1.5 or more and 2.0 or less.
  • [Scandium elution process] sulfuric acid of 0.3N or more and less than 3N is brought into contact with the chelate resin that has undergone the aluminum removal step S22 to obtain a scandium eluent in which scandium is eluted from the chelate resin.
  • a scandium eluent it is preferable to maintain the normality of the sulfuric acid solution used as the elution solution in the range of 0.3N or more and less than 3N, and more preferably in the range of 0.5N or more and less than 2N. preferable.
  • chromium removal process In the chromium removing step S24, sulfuric acid of 3N or more is brought into contact with the chelate resin that has undergone the scandium elution step S23, and the chromium adsorbed when adsorbed on the chelate resin in the adsorption step S21 is removed.
  • chromium if the normality of the sulfuric acid solution is less than 3N, chromium is not properly removed from the chelate resin, which is not preferable.
  • the higher the concentration of the target component in the extraction starting solution the better the separation performance with impurities other than the target.
  • the amount of scandium to be treated is the same, the amount of the extraction starting solution containing scandium at a higher concentration requires a smaller amount of liquid to be subjected to the solvent extraction treatment, and as a result, the amount of substance of the extractant to be used is also increased. Can be reduced. Further, there are various merits such as improvement of operation efficiency such that the equipment required for the solvent extraction process can be made more compact.
  • a neutralizing agent is added to the scandium eluent in order to increase the scandium concentration in the scandium eluent, that is, to concentrate the scandium.
  • the pH is adjusted to form a scandium hydroxide precipitate, and an acid is added to the obtained scandium hydroxide precipitate to dissolve it again. This makes it possible to obtain a solution having a high scandium concentration (extraction starting solution).
  • the processing efficiency of the solvent extraction can be improved.
  • a scandium-containing precipitate is once formed from the scandium eluent and solid-liquid separated, so that the effect of separating impurities that did not become a precipitate is also expected. it can.
  • the neutralization step S3 was obtained as a neutralization step S31 in which the scandium eluent was neutralized to obtain a neutralized starch and a neutralized filtrate. It has a hydroxide dissolution step S32, which dissolves the neutralized starch by adding an acid to obtain a redissolved solution (hydroxide solution) containing a high concentration of scandium.
  • the scandium eluent is neutralized and the pH of the eluent is adjusted to a predetermined range to make scandium contained in the scandium eluent a precipitate of scandium hydroxide. .. Then, in the scandium recovery method according to the present embodiment, in this neutralization step S31, a neutralization treatment is performed by adding a neutralizing agent and dimethylglyoxime to the scandium eluent.
  • the impurity elements contained in the scandium eluent are more effectively separated by adding dimethylglyoxime in addition to the neutralizing agent to perform the neutralization treatment. Can be done.
  • nickel as an impurity can be effectively and efficiently separated.
  • the neutralization treatment in the neutralization step S31 it is preferable to perform pH adjustment by neutralization using a neutralizing agent in two steps. This makes it possible to separate impurities more efficiently and concentrate scandium.
  • FIG. 3 is a process diagram showing a flow when performing a two-step neutralization treatment in the neutralization step S31.
  • a neutralizing agent and dimethylglioxime are added to the scandium eluent to perform a neutralization treatment, and the primary neutralized starch and the primary neutralization are performed by solid-liquid separation.
  • a neutralizing agent is further added to the primary neutralization filtrate to perform a neutralization treatment, and a secondary neutralized starch and a secondary neutralized filtrate are obtained by solid-liquid separation.
  • First neutralization step Specifically, as the first neutralization step S311, a neutralizing agent such as sodium hydroxide is added to the scandium eluent to adjust the pH within a predetermined range, and dimethylglyoxime is added. The first step of neutralization is performed to produce a precipitate.
  • a neutralizing agent such as sodium hydroxide is added to the scandium eluent to adjust the pH within a predetermined range, and dimethylglyoxime is added.
  • the first step of neutralization is performed to produce a precipitate.
  • the pH of the solution is adjusted to preferably in the range of 3.8 to 4.5 by adding a neutralizing agent and dimethylglyoxime. To do. Further, more preferably, the pH is adjusted to be about 4.0 to 4.2. By adding a neutralizing agent so that the pH of the scandium eluent is in such a range, scandium can be more efficiently concentrated in the primary neutralization filtrate.
  • the pH of the solution to be adjusted it is preferable that it is close to the neutral region in order to promote the rightward reaction in the above formula [1]. From this, if the pH is less than 3.8, there is almost no acid dissociation of dimethylglyoxime, and there is a possibility that a precipitate of bis (dimethylglyoximeto) nickel is not sufficiently formed. On the other hand, when the pH is higher than 4.5, the amount of scandium hydroxide precipitated increases, so that nickel and scandium may not be effectively separated.
  • the neutralizing agent is not particularly limited as long as the scandium eluate can be adjusted to a desired pH range, and examples thereof include sodium hydroxide.
  • the amount of dimethylglioxime added is not particularly limited, but is preferably 3 equivalents to 50 equivalents with respect to the amount of nickel contained in the scandium eluent, and 4 equivalents to 40 equivalents. Is more preferable, and the ratio is more preferably 10 equivalents to 35 equivalents.
  • a neutralizing agent such as sodium hydroxide is further added to the primary neutralization filtrate obtained by the first-stage neutralization, and the pH of the solution is predetermined.
  • the second stage of neutralization is performed so that the range is adjusted.
  • the pH of the primary neutralization filtrate is adjusted to preferably in the range of 5.5 to 6.5 by adding a neutralizing agent. Further, more preferably, the pH is adjusted to be about 6.0. By adding a neutralizing agent so that the pH of the primary neutralizing filtrate is in such a range, a precipitate of scandium hydroxide can be produced more efficiently.
  • the neutralizing agent is not particularly limited as long as the primary neutralizing filtrate can be adjusted to a desired pH range, and examples thereof include sodium hydroxide solution.
  • the concentration of the neutralizing agent such as sodium hydroxide solution may be appropriately determined.
  • the neutralizing agent such as sodium hydroxide solution
  • the neutralizing agent is preferably a solution diluted to 4N or less, whereby the neutralization reaction may be uniformly caused.
  • the concentration of the neutralizing agent such as sodium hydroxide solution is too low, the amount of solution required for addition will increase by that amount, the amount of liquid to be handled will increase, and as a result, the equipment scale will increase and the cost will increase. It is not preferable to cause it. Therefore, it is preferable to use a neutralizing agent having a concentration of 1N or more.
  • the precipitate obtained by adding an alkaline neutralizing agent such as sodium hydroxide has extremely poor filterability. Is common. Therefore, at the time of neutralization, seed crystals may be added to improve the filterability.
  • the seed crystal is preferably added in an amount of about 1 g / L or more with respect to the solution before the neutralization treatment.
  • hydroxide dissolution process In the hydroxide dissolution step S32, an acid is added to the neutralized starch (secondary neutralized starch) containing scandium hydroxide as a main component, which is recovered through the neutralization treatment in the above-mentioned neutralization step S31. A hydroxide solution that dissolves and becomes a redissolve is obtained. In the scandium recovery method according to the present embodiment, the redissolved solution thus obtained is used as the extraction starting solution of the solvent extraction treatment in the solvent extraction step S4 described later.
  • the acid for dissolving the neutralized starch is not particularly limited, but it is preferable to use a sulfuric acid solution.
  • a sulfuric acid solution is used, the redissolved solution is a scandium sulfate solution.
  • a sulfuric acid solution when used, its concentration is not particularly limited, but considering the industrial reaction rate, it is preferable to dissolve using a sulfuric acid solution having a concentration of 2N or more.
  • an extraction starting solution having an arbitrary scandium concentration can be obtained.
  • the pH of the solution is preferably maintained in the range of 0.8 to 1.5, more preferably about 1.0.
  • the dimethylglyoxime recovery step S33 is provided, and the dimethylglyoxime remaining in the solution is recovered from the neutralization filtrate obtained through the neutralization step S31. can do.
  • a flow of performing a two-step neutralization treatment and recovering dimethylglyoxime dissolved in the secondary neutralization filtrate obtained through the treatment in the second neutralization step S312 is illustrated.
  • the dimethylglyoxime recovery step S33 is not limited to the neutralization filtrate obtained through the two-step neutralization treatment, and is also preferably a treatment step for the neutralization filtrate obtained through the neutralization treatment of only one step, for example. Can be provided.
  • a compound containing nickel is added to the neutralized filtrate, and dimethylglyoxime and nickel are reacted to produce a precipitate of bis (dimethylglyoximeto) nickel.
  • the method can be mentioned.
  • by adding an acid and mixing the obtained precipitate so that the pH becomes less than 3.8 only nickel is dissolved in the acid solution, and dimethylglyoxime remains as a precipitate without being dissolved. And can be separated from nickel to recover dimethylglyoxime.
  • the recovered dimethylglyoxime can be reused as dimethylglyoxime used in the neutralization step S31 (indicated by the arrow R in FIG. 3), and the drug cost can be effectively reduced.
  • the solvent extraction treatment is performed on the eluent (extraction starting solution) after neutralization.
  • the neutralized eluent refers to a solution obtained by subjecting the scandium eluent obtained in the scandium elution step S2 to the neutralization treatment in the neutralization step S31. More specifically, a redissolved solution (hydroxide solution) obtained through the neutralization step S3 is used as the eluent after neutralization, and the solution is brought into contact with an extractant to perform solvent extraction treatment. A drawing residue containing scandium is obtained.
  • the redissolving solution used for solvent extraction is an acidic solution in which scandium is concentrated, and is also referred to as a "scandium-containing solution" below.
  • the treatment mode in the solvent extraction step S4 is not particularly limited, but as shown in FIGS. 1 and 2, for example, a scandium-containing solution and an extractant which is an organic solvent are mixed to selectively select impurities in the organic solvent.
  • Extraction step S41 to obtain a drawing residue with scandium left
  • scrubbing step S42 to mix a sulfuric acid solution with an organic solvent after extraction and wash the organic solvent after extraction, and a back extractant to the organic solvent after cleaning. It is preferable to carry out the solvent extraction treatment including the back extraction step S43 in which impurities are back-extracted from the organic solvent after washing by adding the above.
  • extraction process In the extraction step S41, an organic solvent containing an extractant and a scandium-containing solution are mixed, impurities are selectively extracted into the organic solvent, and the post-extraction organic solvent containing the impurities and the extract residue liquid containing scandium are left. And get.
  • a solvent extraction treatment using an amine-based extractant is preferably performed. By performing the solvent extraction treatment using the amine-based extractant in this way, impurities can be extracted more efficiently and effectively and separated from scandium.
  • Amine-based extractants have features such as low selectivity with scandium and no need for a neutralizer during extraction.
  • Examples of the amine-based extractant include PrimeneJM-T, which is a primary amine, LA-1, which is a secondary amine, TNOA (Tri-n-octylamine), which is a tertiary amine, and TIOA (Tri-i-octylamine). Those known by the trade name of can be used.
  • the amine-based extractant At the time of extraction, it is preferable to dilute the amine-based extractant with, for example, a hydrocarbon-based organic solvent or the like before use.
  • concentration of the amine-based extractant in the organic solvent is not particularly limited, but is preferably about 1% by volume to 10% by volume in consideration of phase separation during extraction and back-extraction described later. In particular, it is more preferably about 5% by volume.
  • the volume ratio of the organic solvent to the scandium-containing solution at the time of extraction is not particularly limited, but the molar amount of the organic solvent is increased to about 0.01 to 0.1 times the amount of metal in the scandium-containing solution. It is preferable to do so.
  • a sulfuric acid solution As the solution (cleaning solution) used for scrubbing, a sulfuric acid solution, a hydrochloric acid solution, or the like can be used. In addition, water to which soluble chloride or sulfate is added can also be used. Specifically, when a sulfuric acid solution is used as the cleaning solution, it is preferable to use a solution having a concentration in the range of 1.0 mol / L to 3.0 mol / L.
  • the impurities are back extracted from the organic solvent from which the impurities were extracted in the extraction step S41.
  • a back extraction solution back extraction starting solution
  • the impurities are back-extracted to obtain a solution after back-extraction containing the impurities.
  • the back extraction solution is preferably a solution containing a carbonate such as sodium carbonate or potassium carbonate.
  • the concentration of the carbonate-containing solution which is a back-extraction solution, is preferably about 0.5 mol / L to 2 mol / L, for example, from the viewpoint of suppressing excessive use.
  • the back-extraction treatment is similarly performed by adding the back-extraction solution to the scrubbing extractant and mixing it. It can be carried out.
  • impurities can be removed from the extractant again by adding a carbonate solution such as sodium carbonate to the extractant after extraction or the extractant after scrubbing and performing the back extraction treatment. , Can be repeated as an extractant used in the extraction process.
  • a carbonate solution such as sodium carbonate
  • the method for crystallizing and recovering scandium is not particularly limited, and a known method can be used.
  • a method of producing and recovering a oxalate precipitate using an oxalic acid solution (oxalate treatment) can also be used. According to these methods, impurities contained in the extraction residue can be effectively separated to obtain high-purity scandium crystals.
  • roasting step S52 the precipitates such as scandium hydroxide and scandium oxalate obtained in the crystallization step S51 are washed with water, dried, and then roasted. By undergoing this roasting treatment, scandium can be recovered as extremely high-purity scandium oxide.
  • the conditions of the roasting treatment are not particularly limited, but for example, it may be placed in a tube furnace and heated at about 900 ° C. for about 2 hours. Industrially, it is preferable to use a continuous furnace such as a rotary kiln because drying and roasting can be performed by the same apparatus.
  • Example 1 (Hydrometallurgy step S1) A pressure acid leaching treatment with sulfuric acid was performed using nickel oxide ore as a raw material, the pH of the obtained leachate was adjusted to remove impurities, and then a sulfurizing agent was added to separate nickel to prepare a post-sulfurized liquid. .. Table 1 below shows the concentrations of scandium (Sc), aluminum (Al), and iron (Fe) in the obtained post-sulfidation liquid.
  • the neutralizing agent is added until the pH of the solution reaches 4.2, and dimethylglyoxime is added to perform the neutralization treatment.
  • Chromium could be effectively precipitated as a neutralizing starch.
  • nickel could be effectively separated from scandium distributed in the primary neutralization filtrate.
  • solvent extraction step S4 Next, 500 ml of the obtained hydroxide solution was used as the extraction starting solution, and an amine-based extractant (PrimeneJM-T, manufactured by Dow Chemical Co., Ltd.) was used as a solvent (Shellzol A150, manufactured by Shell Chemicals Japan Co., Ltd.). 250 ml of an organic solvent adjusted to 5% by volume was mixed, and the mixture was stirred at room temperature for 60 minutes to perform solvent extraction treatment (extraction step S41). By this solvent extraction treatment, a extraction residual liquid containing scandium was obtained. At the time of extraction, no clad was formed, and phase separation after standing proceeded rapidly.
  • an amine-based extractant (PrimeneJM-T, manufactured by Dow Chemical Co., Ltd.) was used as a solvent (Shellzol A150, manufactured by Shell Chemicals Japan Co., Ltd.).
  • a sulfuric acid solution having a concentration of 1 mol / L was added to 250 ml of an organic solvent (extracted organic phase) containing a small amount of scandium obtained after the extraction treatment so that the phase ratio (O / A) was 1.
  • the mixture was mixed in an amount of 250 ml, stirred for 60 minutes and washed. Then, the mixture was allowed to stand to separate the aqueous phase, and the organic phase was washed again by mixing with 250 ml of a new sulfuric acid solution having a concentration of 1 mol / L, and the aqueous phase was separated in the same manner.
  • Such a cleaning operation was repeated a total of 5 times (scrubbing step S42).
  • the scandium contained in the extracted organic phase could be separated into the aqueous phase and recovered.
  • the impurities contained in the extracted organic phase only the elution at a low level of 1 mg / L can be achieved, and only the scandium extracted in the organic solvent can be effectively separated into the aqueous phase, and only the impurities can be removed. It was.
  • the obtained scandium oxalate precipitate was suction-filtered, washed with pure water, and dried at 105 ° C. for 8 hours.
  • the dried scandium oxalate was placed in a tube furnace and roasted (calcined) at 850 ° C. to 900 ° C. to obtain scandium oxide.
  • Example 2 The post-sulfurized solution of the same composition shown in Table 1 used in Example 1 was subjected to ion exchange treatment in the same manner as in Example 1 to obtain a scandium eluate having the same composition as in Table 2 above.
  • the obtained scandium eluent is placed in a reaction vessel, and dimethylglyoxime is added at a ratio corresponding to 5 equivalents of a sodium hydroxide solution having a concentration of 4 N and the amount of nickel present in the scandium eluent while stirring to make a solution.
  • the first-stage neutralization treatment was performed to adjust the pH of the mixture to 4.3.
  • Example 1 The post-sulfurized solution of the same composition shown in Table 1 used in Example 1 was subjected to ion exchange treatment in the same manner as in Example 1 to obtain a scandium eluate having the same composition as in Table 2 above.
  • the obtained scandium eluent is placed in a reaction vessel, a sodium hydroxide solution having a concentration of 4 N is added with stirring, and a neutralization treatment is performed to adjust the pH of the solution to 6, and a precipitate (neutralized starch) is applied.
  • the product) and the neutralized filtrate were produced. That is, unlike Examples 1 and 2, dimethylglyoxime was not added and only one step of neutralization treatment was performed.
  • the obtained scandium oxide was analyzed by luminescence spectroscopy.
  • Table 11 shows the grade (ppm) of each impurity contained in scandium oxide.
  • the content of nickel was particularly high among the impurity elements.
  • Comparative Example 1 in the neutralization treatment for the scandium eluate, only the sodium hydroxide solution as a neutralizing agent was added, and dimethylglyoxime was added to the neutralizing agent. It is probable that nickel was not sufficiently removed as a precipitate because nickel was not added because oxime was not added.
  • Example 3 (Hydrometallurgy step S1) Using the same nickel oxide ore as in Example 1 above as a raw material, pressure acid leaching is performed using the same method as in Example 1, the pH of the obtained leachate is adjusted to remove impurities, and a sulfurizing agent is added. After addition, nickel was separated to prepare a post-sulfurization liquid (a post-sulfidation liquid having the same composition as in Table 1 above).
  • the neutralizing agent was added until the pH of the solution reached 4.0, and dimethylglyoxime was added to perform the neutralization treatment.
  • Chromium could be effectively precipitated as a neutralizing starch.
  • nickel could be effectively separated from scandium distributed in the primary neutralization filtrate.
  • scandium which is a recovery loss, could be halved.
  • solvent extraction step S4 Next, 500 ml of the obtained hydroxide solution was used as the extraction starting solution, and an amine-based extractant (PrimeneJM-T, manufactured by Dow Chemical Co., Ltd.) was used as a solvent (Shellzol A150, manufactured by Shell Chemicals Japan Co., Ltd.). 250 ml of an organic solvent adjusted to 5% by volume was mixed, and the mixture was stirred at room temperature for 60 minutes to perform solvent extraction treatment (extraction step S41). By this solvent extraction treatment, a extraction residual liquid containing scandium was obtained. At the time of extraction, no clad was formed, and phase separation after standing proceeded rapidly.
  • an amine-based extractant (PrimeneJM-T, manufactured by Dow Chemical Co., Ltd.) was used as a solvent (Shellzol A150, manufactured by Shell Chemicals Japan Co., Ltd.).
  • a sulfuric acid solution having a concentration of 1 mol / L was added to 250 ml of an organic solvent (extracted organic phase) containing a small amount of scandium obtained after the extraction treatment so that the phase ratio (O / A) was 1.
  • the mixture was mixed in an amount of 250 ml, stirred for 60 minutes and washed. Then, the mixture was allowed to stand to separate the aqueous phase, and the organic phase was washed again by mixing with 250 ml of a new sulfuric acid solution having a concentration of 1 mol / L, and the aqueous phase was separated in the same manner.
  • Such a cleaning operation was repeated a total of 5 times (scrubbing step S42).
  • the scandium contained in the extracted organic phase could be separated into the aqueous phase and recovered.
  • the impurities contained in the extracted organic phase only the elution at a low level of 1 mg / L can be achieved, and only the scandium extracted in the organic solvent can be effectively separated into the aqueous phase, and only the impurities can be removed. It was.
  • the obtained scandium oxalate precipitate was suction-filtered, washed with pure water, and dried at 105 ° C. for 8 hours.
  • the dried scandium oxalate was placed in a tubular furnace and roasted (calcined) at 850 ° C. to 900 ° C. to obtain scandium oxide.
  • Example 4 The secondary neutralization filtrate obtained by the same method as in Example 1 above was subjected to the dimethylglyoxime recovery step shown below.
  • (Dimethylglyoxime recovery step S33) First-stage neutralization That is, the secondary neutralization filtrate after separating the secondary neutralization starch containing scandium is collected, placed in a container, and while stirring, a sodium hydroxide solution having a concentration of 8N and 1 A process of recovering dimethyl glyoxime by adding nickel sulfate in a ratio corresponding to 9 equivalents of the amount of dimethyl glyoxime added in the stage neutralization treatment to adjust the pH of the solution to 6.0. (Neutralization treatment) was performed.
  • the neutralized starch (bis (dimethylglioxymato) nickel starch) obtained by the first-stage neutralization is stirred while adding 64% sulfuric acid and pure water. , A lysate and a lysate were obtained.
  • the analysis was performed using ICP, and the ratio (distribution) of the amount dissolved in the filtrate to the amount contained in the neutralized starch was evaluated as the dissolution rate (%). As a result, the dissolution rate of nickel was 82%.
  • nickel in the bis (dimethylglyoximeto) nickel starch which is a neutralized starch, dissolves in the acid and is distributed to the solution, but dimethylglyoxime does not dissolve in the acid. Recovered as starch.
  • Example 5 (Reuse of dimethylglyoxime)
  • the dimethylglyoxime recovered by the operation of Example 4 was returned to the first neutralization step S311 in the neutralization step S31 and reused.
  • dimethylglyoxime adjusted to 10 equivalents of the amount of nickel present in the scandium eluent to be neutralized by adding new dimethylglyoxime to the recovered dimethylglyoxime is added to the scandium eluent. Then, a sodium hydroxide solution having a concentration of 4N was added with stirring to adjust the pH of the solution to 4.2. By this neutralization treatment, a nickel bis (dimethylglioxymate) precipitate was obtained as the primary neutralized starch.
  • the obtained precipitate is analyzed using ICP, and the ratio (distribution) of the amount of the precipitate produced to the amount contained in the nickel sulfate solution before the neutralization treatment is evaluated as the precipitation rate (%). did.
  • the precipitation rate of nickel was 99%, and it was confirmed that most of the nickel was precipitated.
  • the recovered dimethylglyoxime can be effectively reused.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Geochemistry & Mineralogy (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

La présente invention concerne un procédé destiné à récupérer du scandium, le procédé permettant de récupérer efficacement du scandium à haute pureté d'une solution qui contient des impuretés ainsi que du scandium.　La présente invention est un procédé destiné à récupérer du scandium, ledit procédé consistant : en une étape de neutralisation (S3) selon laquelle une solution contenant du scandium est passée à travers une résine d'échange d'ions, un éluant élué depuis la résine d'échange d'ions est neutralisé en y ajoutant un agent neutralisant et de la diméthylglyoxime, et ensuite un sédiment neutralisé et un filtrat neutralisé sont obtenus par séparation solide-liquide ; en une étape d'extraction de solvant (S4) selon laquelle l'éluant après neutralisation est soumis à un traitement d'extraction de solvant ; et en une étape de récupération de scandium (S5) selon laquelle de l'oxyde de scandium est récupéré d'un résidu d'extraction qui est séparé au moyen d'un traitement d'extraction de solvant.
PCT/JP2020/033775 2019-09-24 2020-09-07 Procédé destiné à récupérer du scandium WO2021059942A1 (fr)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
JP2019173050 2019-09-24
JP2019-173050 2019-09-24
JP2020-027793 2020-02-21
JP2020027793 2020-02-21
JP2020-091441 2020-05-26
JP2020091441A JP7327276B2 (ja) 2019-09-24 2020-05-26 スカンジウムの回収方法

Publications (1)

Publication Number Publication Date
WO2021059942A1 true WO2021059942A1 (fr) 2021-04-01

Family

ID=75165752

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2020/033775 WO2021059942A1 (fr) 2019-09-24 2020-09-07 Procédé destiné à récupérer du scandium

Country Status (1)

Country Link
WO (1) WO2021059942A1 (fr)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4843405B1 (fr) * 1970-07-23 1973-12-18
JPS6333530A (ja) * 1986-07-23 1988-02-13 Sumitomo Metal Ind Ltd ニツケルの回収方法
JPH09194211A (ja) * 1996-01-18 1997-07-29 Taiheiyo Kinzoku Kk 酸化鉱石からの高純度レアーアースメタル酸化物の製造方法
WO2017130692A1 (fr) * 2016-01-25 2017-08-03 住友金属鉱山株式会社 Procédé de récupération du scandium
JP2018204088A (ja) * 2017-06-08 2018-12-27 住友金属鉱山株式会社 スカンジウムの回収方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4843405B1 (fr) * 1970-07-23 1973-12-18
JPS6333530A (ja) * 1986-07-23 1988-02-13 Sumitomo Metal Ind Ltd ニツケルの回収方法
JPH09194211A (ja) * 1996-01-18 1997-07-29 Taiheiyo Kinzoku Kk 酸化鉱石からの高純度レアーアースメタル酸化物の製造方法
WO2017130692A1 (fr) * 2016-01-25 2017-08-03 住友金属鉱山株式会社 Procédé de récupération du scandium
JP2018204088A (ja) * 2017-06-08 2018-12-27 住友金属鉱山株式会社 スカンジウムの回収方法

Similar Documents

Publication Publication Date Title
JP5967284B2 (ja) 高純度スカンジウムの回収方法
US9963762B2 (en) Scandium recovery method
JP6798078B2 (ja) イオン交換処理方法、スカンジウムの回収方法
JP6439530B2 (ja) スカンジウムの回収方法
CA3007373C (fr) Procede permettant la recuperation de scandium
JP6172099B2 (ja) スカンジウムの回収方法
WO2017135245A1 (fr) Procédé de récupération du scandium
US10196710B1 (en) Method for recovering scandium
JP6816410B2 (ja) スカンジウムの回収方法
WO2016084830A1 (fr) Procédé de récupération de scandium haute pureté
WO2021059942A1 (fr) Procédé destiné à récupérer du scandium
JP7327276B2 (ja) スカンジウムの回収方法
JP6206358B2 (ja) スカンジウムの回収方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20870199

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20870199

Country of ref document: EP

Kind code of ref document: A1